The predicates in this section explore the rdfs:subPropertyOf,
rdfs:subClassOf and rdf:type relations. Note 
that the most fundamental of these, rdfs:subPropertyOf, is 
also used by rdf_has/[3,4].
rdfs:subPropertyOf relation. It can be used to test as well 
as generate sub-properties or super-properties. Note that the commonly 
used semantics of this predicate is wired into rdf_has/[3,4].bugThe 
current implementation cannot deal with cycles.bugThe 
current implementation cannot deal with predicates that are an rdfs:subPropertyOf 
of rdfs:subPropertyOf, such as owl:samePropertyAs.rdfs:subClassOf relation. It can be used to test as well as 
generate sub-classes or super-classes.bugThe 
current implementation cannot deal with cycles.rdf:type property that refers to
Class or a sub-class thereof. Can be used to test, generate 
classes Resource belongs to or generate individuals described 
by Class.